I think there's no known medical/neurological proof of that - an actual common pool of information.
I think it's more to do with how our brains are hardwired - we interpret the world alike, therefore we create images/myths that are alike.
I'm not so sure.
Have you heard of Rupert Sheldrake?
While I disagree with Sheldrake's interpretation of "Morphogenic Fields" his research points to some sort of common consciousness or "pool of information" of some other mechanism of sharing information...
Excerpt from:
Memory And Morphogenetic Fields
by Robert Gilman
Originally published in IN CONTEXT #6, Summer 1984, Page 11 Copyright (c)1984, 1997 by Context Institute
http://twm.co.nz/shel_morfields.htm
In the meantime, the puzzles about memory have grown even stranger. This part of our story will take us to one of the most controversial frontiers of current science, although it actually starts back in 1920 when W. McDougall, a biologist at Harvard, began an experiment to see if animals (in this case white rats) could inherit learning. The procedure was to teach the rats a simple task (avoiding a lighted exit), record how fast they learned, breed another generation, teach them the same task, and see how their rate of learning compared with their elders. He carried the experiment through 34 generations and found that, indeed, each generation learned faster in flat contradiction to the usual Darwinian assumptions about heredity. Such a result naturally raised controversy, and similar experiments were run to prove or disprove the result. The last of these was done by W.E. Agar at Melbourne over a period of 20 years ending in 1954. Using the same general breed of rats, he found the same pattern of results that McDougall had but in addition he found that untrained rats used as a control group also learned faster in each new generation. (Curiously, he also found that his first generation of rats started at the same rate of learning as McDougall's last generation.) No one had a good explanation for why both trained and untrained should be learning faster, but since this result did not support the idea that learning was inherited, the biology community breathed a sigh of relief and considered the matter closed.
There it stayed until 1981 when another biologist, Rupert Sheldrake, proposed a radical new interpretation in his book, A New Science Of Life (Los Angeles: J.P. Tarcher, 1982). Sheldrake's larger concern was with what biologists have for years called "morphogenetic fields." Morphogenetic means "giving birth to form," and some biologists hypothesized that, in order to explain how plants and animals grow into the forms that they have, something more than just the usual rules of physics and chemistry was needed. They described this unknown something as a "morphogenetic field." Of course, other biologists thought this was all hogwash and were convinced that an appropriately detailed application of the rules of physics would explain all of biology. In recent decades most biologists held this second position, but Sheldrake may be changing all that.
What Sheldrake has done is threefold. He has linked the longstanding biological problems of form with similar problems in areas as diverse as crystal growth and psychology. He has proposed plausible rules for how morphogenetic fields might behave. And he has suggested how his theory could be tested and shown how existing experiments, like the McDougall-Agar series, support his theory.
--related info--
In 1920 William McDougall of Harvard began training rats to learn to escape from a water maze by choosing the correct exit. While the brightly lit exit would give them an electric shock, when they picked the dimly-lit exit, they got out undisturbed. McDougall found that the first generation of rats had to endure 165 shocks before getting the message. But by the 30th generation, only 20 transgressions were necessary to persuade the rats of the error in their way. (McDougall, 1938. British Journal of Psychology 28:321-345.)
McDougall assumed the rats were passing on acquired characteristics. Wishing to disprove this "Lamarckian" (and Darwinian) interpretation of the data, F. A. E. Crew replicated the experiment in Edinburgh. Right from the get-go, Crew's rats needed only 25 errors to learn their lesson, as if picking up where the Harvard rats had left off. (Crew, 1936. Journal of Genetics 33:61-101.)
In Melbourne, W. E. Agar found the same effect. His trials went on for over twenty years, and even when he tested control subjects that weren't descended from trained rats, they still showed improvement over the performance of previous generations. So it couldn't have been coming from their parents. (Agar, 1954. Journal of Experimental Biology 31:307-321.)
http://jeb.biologists.org/search.dtl
Acquired traits have often been observed to pass throughout a species with no known means of direct transfer from individual to individual. For instance, in England in the 20s a small bird known as the blue tit learned to open milk bottles at doorsteps. When one bird learned the trick, others in the area learned it by simple imitation. But the blue tit doesn't fly more than a few miles, and this habit spread to several widely disparate areas in England by 1935 and continued popping up in faraway places throughout the forties, including Scandinavia and Holland. The habit appeared independently at least 89 times in the British Isles, and the spread of the habit accelerated as time went on. (Fisher and Hinde, 1949. British Birds 42:347-357.) Milk bottles practically disappeared in Holland during the war, and by the time they returned all the birds that had been opening them before the war could not have survived to see their return. Yet the habit rapidly returned when the bottles were re-introduced in 1947.
Arden Mahlberg, a psychologist, carried out a test of the ability to learn Morse Code. He had one group of subjects learn actual Morse Code, while another had to learn a newly-invented code that closely resembled it. He found that subjects were able to learn the actual code far more rapidly than the alternative, and he interpreted this as evidence that the subjects
were resonating with the millions of people who had already learned Morse code. Each time he replicated the experiment, he found that the difference in learning time between Morse code and the new one progressively decreased. This might mean that the initial results were false. But the fact that the decrease was progressive suggests that the morphic resonance of the new code was becoming progressively stronger as more and more students learned it. (Mahlberg, 1987. Journal of Analytical Psychology 32:23-34.)
There've been a few experiments roughly along the lines you suggest. For instance, Gary Schwartz, a psychology professor at Yale, selected 48 words from the Hebrew Old Testament. He then scrambled these words to produce 48 more, none of which were real words in Hebrew. He asked test subjects to guess their meaning in English and then rate on a scale of 0 to 4 how confident they felt about whether they'd guessed the meaning correctly. The subjects reported feeling confident about their guesses 75% more often with the real Hebrew words than with the fakes.
Alan Pickering of Hatfield Polytechnic in England came up with a list of authentic Persian words and then created another list of fake words also written in Persian script. He would show each word to the test subjects for ten seconds, after which they would try to duplicate the word on paper. He found that his students were able to duplicate real Persian words more accurately than fake ones 75% of the time. He noted that the odds of achieving this result were 10,000 to 1. Like Schwartz, Pickering concluded that his results confirmed morphic resonance.
